This invention relates to dynamometers and, more specifically, to dynamometers employing disc brake assemblies.
Manufacturers of large motive apparatus, such as construction vehicles, almost invariably test each unit produced to ensure that it is performing satisfactorily and up to its rated capability. In the case of construction vehicles, such testing has typically been performed on a test track or the like and great reliance is placed on the subjective judgement of the operator of the vehicle in determining whether the vehicle is satisfactory for shipping to a customer.
In order to obtain a more reliable measure of a vehicle's capability by eliminating the subjectivity involved on the part of the operator, it is highly desirable to utilize testing equipment, such as dynamometers, to provide more accurate measurement of torque outputs, matching of drive systems in hydrostatic drive systems, etc. However, it has been generally impossible to accomplish such measurement through the use of dynamometers in that the outputs of such vehicles frequently have high torque outputs at relatively low speeds, making measurement very difficult. While dynamometers have been proposed which are capable of performing inaccurate testing functions on such vehicles, they have been quite expensive to the point where the cost has proved to be virtually an absolute deterrent to their use.
Recently, the assignee of the present application has developed a low cost dynamometer suitable in testing such vehicles and which is based on the use of an oil-cooled, disc brake of the type frequently employed in large, off-the-road trucks. It appears that such dynamometers would prove quite successful in reliably testing large vehicles or other rotary mechanisms having rotary outputs which are of large size. However, due to the size of the disc brakes available for incorporation in such dynamometers, their use is limited to the testing of vehicles or the like of intermediate size or smaller. That is, the brake capacity of the disc brakes used therein is insufficient to enable such dynamometers to be employed in the testing of the behemoths of the product line.
Thus, there remains a need for a low cost dynamometer particularly suitable for monitoring rotary outputs of rotary mechanisms having high torque and relatively low output speeds and which are extremely large in size.